Just picked up a Cobra 138XLR....check this out

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I'm just taking it apart to clean it and replace the meter light and touch up the faded meter.
Look at those WW2 submarine relays...they are a gold colored metal can, anyone seen that before?
It has a stock appearance till you plug a dummy jack in the PA jack then the CB/PA and NB/ANL switches go from stock operation to "modded".
Pretty stealth.

Compared to my 449 this radio is really well built, it puts out a full 20W no sweat and even has a power choke on the speaker plate.
First 858 Cobra I ever had.

I'll be putting the 449 on CL and using this for now on I think, it is just better built thats for sure.

 

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looks like pins 21, 20, 19, 18, 16 and 13 are tapped....

 

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Seems like alot of work for a few uppers and 10kc switch....

 

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I see someone did the wideband TX mod but instead of using the unused pin, they cut the trace and jumped a ceramic cap across and only did the one side.....interesting.

 

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I found very little info on those relays, they are for airplanes.

CARRIERE AND MACFEETERS, LTD.
,51 Front St.E.,Toronto.
—
Overhaul and repair of aircraft electrical accessories and telecommunications equipment.
Contractors to Dept. of Defense Production and commercial aviation companies, employing
75 people and covering 15,000 sqft plant space

Since the company's formation in 1948, production has increased by at least 50 percent each year

 

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The way this mod is done, it gets channel 1-7 are 365-445 then 8-40 are 455 to 805 on anl with a 10kc shift on the cb/pa

 

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More pics of the 449 and 138xlr for comparison.

 

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Can anyone confirm tr 8, 9 and 10 to be 2sc839's?
The parts list says 1675

 

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Well I deep 6'd the WW2 relays, maybe tin whiskers in it who knows but when switching the "extras" on and off the s-meter would refuse to move till I keyed up and whistled.
I didn't like that so I wired pin 21 to the NB/ANL switch via a 1n914 and did pin 17(41-45) switch down and pin 19(45-80) switch up with normal in the middle.

I managed to finesse a 29xlr NB/ANL switch into the CB/PA slot without touching the faceplate, I just used my soldering iron to carve the plastic shaft down a bit to clear the square hole in the metal chassis, it goes up/down 10KC.

I also added a pull-out switch pot on the rf gain for the NB-pull out is off.

Now I have the same coverage but without the s-meter bug that that old mod was doing.
Looking at the pictures it looks kinda nasty, but I triple checked it and its solid....maybe my 30W iron is too hot.

 

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I have since removed this red wire from pin 21 (it's not 5V all the time like I thought) and moved it to the trace coming from pin 7.

 

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Great radio. I like the tone control. Mine shows some usage, but still works like a champ

 

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http://www.ebay.ca/itm/VINTAGE-COBR...8031334&pid=100011&rk=1&rkt=3&sd=321922485880

Mint condition